More a trial run than a tent pole, something to dip their toe into the waters of original online video content.
I’ve read somewhere that Apple is spending over billion dollars on content for its subscription tv offering which will launch next year sometime. Carpool Karaoke is definitely just a minor show they cranked out while they were getting their feet wet with this whole original video content thing.
ETA: ok, a mere 900 million. With 4+ billion more scheduled between now and 2022.
https://www.investors.com/news/technology/click/apple-streaming-video-tv-aapl/